Process of preparing substituted malonic acids



Patented June 25, 1935 UNITED STATE-s PROCESS or PREPARING SUBSTITUTED VMALONTIC ACIDS 2 Paul. Halbig and Felix Kaufler, Munich, ,Ger-

many, assignors to Dr.. Alexander Wacker. Gesellschaft fiir Elektrochemische,Industrie,, G. in. b. H Munich, Germany, a corporation N0. Drawing. Application May 25, 1933, Serial No. 672,866. In Germany June 8, 1932 14 c aims. (011260-116) f Y M This invention relates'to lower alkyl substituted malonic. acids. 4 I

i We have. discovered that substituted malonic acid,containing nitric oxide .or higher nitrogen.

oxide, or a mixture of such oxides, nitric acid'fi sulphuric acid mixtures, sulphuric acid containing. nitric oxide. or higher nitrogen oxide, or'a mixture of such oxides, etc., may be used as the oxidizing agent. Vanadium and molybdenum compounds such .as ammonium .vanadate, 'am-i monium molybdate, etc., may. be used as oxidation catalysts. a g u-The water :insoluble corresponding. oxy .901 aldehyde compounds are treated with the acid containing the nitrogen oxide, preferably at between 10 and.50 C.,v thenitrogen oxide giving. up some of its oxygen and being changedto a lower. nitrogen oxide, and the derivative is oxidized to a substituted ,malonid. acid. The lower nitrogen oxide formed can be regenerated by treatment with oxygen or an oxygen containing gas, and

-preferably this regeneration is effected in the reaction apparatus. With regeneration, there is practically no loss of nitrogen oxide, only oxygen being used up in the process.

The substituted malonic acid crystallizes in a very pure condition either with or without concentration of the mother liquor, and after removal and drying of the crystals no purification is necessary.

Example 1 the mother liquor cooled to about 0. C.; The crystals are suction-filtered and dried, 212- grams of the same of 121 C. ,meltingpoint being ob; tained. Upon concentration of the mother liquor I an:..additional 14 gramscrystallizes out. The 5. yield correspondsto about 89% of theory.

"Ea:ample 2 1 319 grams of "2,2rdiethyl propanol-(D al-(3) are dropped into 600 grams of nitric acid. containing nitric oxide (41:1.4) at 15 to-.20 C,.jas in Example}. .375 grams ofdiethyl malonic acid of 120. C. melting point are obtained, corresponding to about;94% of theory.

; ,.r Example 3 w 26 grams of, 2,2-diethyl-propanol- (1) 'a'1'(3)- are gradually-added toz-aimixture'of 44 grams, of. 68% nitric acid,,30 grams of sulphuricacid, traces of nitrogen oxide, andv 0.1 gram of. ammonium,jvanadate at about 40 C., and oxygenis introduced into the solution. 26 grams of diethyl malonic acid crystallizes from the mother liquor, correspondingtoabout of theory. v

In asimilarway substituted malonic acid may be; obtained vfrom 2-ethyl-2-butyl-propanol-(1) al,-; ,(3);, -2-methyl-2eethyl-propandiole(l, 3) ,,2,2..v diethyl-propanol-i l") -acid- ,(3), etc., with; good yield and in a pure, state. :31 a ,We claim as ourinvention: 1-. Process of directly preparing alkylsubsti: tutedrnalonic acids from a corresponding water-g insoluble compound containing in place of at least one carboxyl group'of the substituted ma lonic acid at least one of the group consisting of -CH2OH and CH0, comprising oxidizing said compound with an inorganic acid in the presence of a nitrogen oxide having at least one oxygen atom to one nitrogen atom.

2. Process-of directly preparing a malonic acid substituted with lower alkyl. substituents from a corresponding water-insoluble compound containing in place of at least one carboxyl group of the substituted malonic acid one of the group consisting of -CH2OH and --CHO, comprising oxidizing said compound with an inorganic acid in the presence of a nitrogen oxide having at least one oxygen atom to one nitrogen atom.

3. Process of directly preparing alkyl substituted malonic acids from a corresponding waterinsoluble compound containing in place of. at least one carboxyl group of the substituted ma lonic acid at least one of the group consisting of --CH2OH and -CHO', comprising oxidizing said compound at between 10 and 50 C. with an inorganic acid in the presence of a nitrogen oxide n atom and an oxidation catalyst.

having at least one oxygen atom to one nitrogen atom.

4. Process of directly preparing alkyl substi- 1 tuted malonic acids from a corresponding water-,

insoluble compound containing in placeof at least one carboxyl group of the substituted malonic acid at least one of the group consisting of -CH2OH and CHO,' comprisingoxidizing said compound at between 10 and 50 C. with an in-' organic acid in the presence of a nitrogen oxide having at least one oxygen atom to one nitrogen 5. Process of directly preparing alkyl tuted malonic acids from a'corresponding waterinsoluble compound containinginplace of at least one carboxyl group of the"'substitut'ed malonic acid at least one of the group consisting oi CHzOH and CHO, comprising oxidizing said compound at between 10 and 50 C. with winorganic acid in the presence of a nitrogen oxide having at least-one oxygenatom to -one nitrogen atom and oxidizing" the lower nitrogen oxide formed'in the reaction mixture."

1 compound with nitric acid.-- r r 7. Process of directly preparing alkyl substi-- 6. Process of directly preparing alkyl substi f tuted malonic acids froma corresponding waterinsoluble compound containing in: place of at least one carboxyl group. of the substituted malonic acid at least one of the group consisting of --C HzOH and -'-'CI-IO, comprisin'gfoxidiflng: said tuted malonic acids from'a correspondingwaterinsoluble compound containingioiin' place of at least one carboxyl group of the substituted malonic acid at least one ofthe group consisting of 'CH2OH and CHQ'coinprising oxidizing said. compound with nitric acid in the presence of a 7 one nitrogen atom.

nitrogenoxide havingat least one oxygen atom to 8. Process of directly preparing alkyl substituted malonic acids froma corresponding waternitrogen oxide having at least one oxygen atoni to one nitrogen atom at between 10 and 50 C.

10. Process of preparing ethyl butyl malonic acid comprising treating 2-ethyl-2-butyl-pro-V pano1-(1)-al-(' 3) with nitric acid containing a nitrogen'oxide having at least one oxygen atom to one nitrogen atom at between 10 and 50 C.

11. Process of preparing diethyl malonic acid,

comprising treating 2,2-diethyl-propanol-(1)-a1- -(3)jwith a mixture of nitric acid, sulphuric acid andnitro gen oxide having at least one oxygen atom to one nitrogen atom in the presence of am-' monium v'anada te at'between 10 and 50- C. 7

12 Process of directlypreparing alkyl substituted malonic acids'from a corresponding waterinsoluble compound containing in place of at least one carboxyl group of the substituted malonic acid at least one-0! the group consisting of -CHzOH' and --CHO,;comprising oxidizing said compound at'between' 10 and- 50C. with an inorganicacld in the presence oi a nitrogen oxide having at least one oxygen atom to one nitrogen atom; ox

izing the oxidized nitrogen oxide for the,produc tion of alkyl-substituted malonic aci'd.

13-. Process of directly. preparing alkyl substi tuted malonic acids from a correspondlng'waterinsoluble compound containing in-place of at leastonecarboxyl group of the substituted ma lonic acid at least one oi the group consisting of CH:OH and -VCHO, comprising oxidizingsaid compound at between 10? and 50 C. withaninidizing the, formed lower nitrogen oxide and util organic acid in the presence oi." a nitrogen oxide g having at least one oxygen atom to one nitrogen atom and introducing oxygen into the reaction mixture to oxidize the lower nitrogen oxideiormed therein. v. I i v V r 14. Process of directly, preparing alkyi substituted malonic acids froma corresponding water-- insoluble compound containing in. place plat least one carboxyl group of'thesubstituted'malonic acid at least: one 01. the group'consisting 0t- CH:OH and 'CI-I0,' comprising oxidizing said compound at between 10 and'50 C. withinorganic acid in the presence of a nitrogen oxide having at least oneoxygen atom. to one nitrogen V atom and introducing oxygen-containing gases into the reaction mixture to oxidiz eithe lower nitrogen oxide formed therein. I

PAUL HALBIG.

FELIXJKAUFLER. i 

